Enzyme-triggered controlled process

Fig. 4 Free energy diagram for the two possible situations in enzyme-triggered formation of supramolecular assembly. Left. The enzyme-catalysed reaction and self-assembly process are both favoured independently and therefore uncoupled. Right. Enzyme-triggered self-assembly under thermodynamic control formation of the building blocks is thermodynamically unfavoured in isolation and occurs in reversible fashion when coupled to a sufficiently stable self-assembled structure formation...

Several important advantages have been derived from the knowledge of the state of water obtained from these microemulsion systems (1) better control of crystallization phenomena dictated by interfaces and water [87-90], (2) better control of organic reactions requiring free water such as hydrolysis, and (3) triggered enzymatic processes in which the enzymes are soluble in the water phase and can be activated upon turning the bound water into free water. 

Thus, a brief puff of chemical neurotransmission from a presynaptic neuron can trigger a profound postsynaptic reaction, which takes hours to days to develop and can last days to weeks or even longer. Every conceivable component of this entire process of chemical neurotransmission is a candidate for modification by drugs. Most psychotropic drugs act on the processes that control chemical neurotransmission at the level of the neurotransmitters themselves or of their enzymes and especially their receptors. Future psychotropic drugs will undoubtedly act directly on the biochemical cascades, particularly on those elements that control the expression of pre- and postsynaptic genes. Also, mental and neurological illnesses are known or suspected to affect these same aspects of chemical neurotransmission. 

Calcium, in contrast to magnesium, does not have an important function as an enzyme activator, in accord with its different distribution. It is very important, however, in the control and triggering of biological processes such as muscle contraction and the release of various chemicals, including hormones, defence chemicals and neurotransmitters. This occurs when, in response to some stimulus, the normal selectivity of the cell membrane or the membranes of internal organelles breaks down, and calcium ions are allowed to enter the cell. These bind to specific sites and trigger certain reactions. 

Photoswitchable enzymes could have an important role in controlling biochemical transformations in bioreactors. Various biotechnological processes generate an inhibitor, or alter the environmental conditions (pH, for example) of the reaction medium. Photochemical activation of enzymes that adjust environmental conditions or deplete the inhibitor to a low concentration may maintain the bioreactor at optimal performance. More specifically, integration of the photoswitchable biocataly-tic matrix with a sensory electrode might yield a feedback mechanism in which the sensor element triggers the light-induced activation/deactivation of the photosensitive biocatalyst. 

It is becoming increasingly obvious that the activity of P450 BM3 is controlled both thermodynamically and by structural changes triggered by substrate (fatty acid or NADP(H)) or redox state of the enzyme. The availability of the crystal structures of substrate-free and bound forms allows investigation of the roles of various amino acids in the processes of substrate binding, electron transfer and oxidative catalysis. This can be achieved... 

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